In a power supply device having a control circuit for controlling a current from a power supply source, it is frequently performed to mount electric and electronic components such as a switching element using a semiconductor element and a reactor using a choke coil on the control circuit. However, in such electric and electronic components, usually, if the temperature exceeds a certain temperature, there is a possibility that the operation becomes unstable or the lifespan decreases. Such a problem of temperature rise is likely to occur, in particular, in case where a large heat radiation space from these electric and electronic components cannot be taken, for example, in case where compactification of the whole apparatus is required and a large heat radiation space for a control circuit or a power supply device incorporated therewith cannot be taken.
For example, in a power supply device for a light source using a light emitting diode (hereinafter, sometimes abbreviated as “LED”), as LED light sources become more powerful and highly integrated, there is a problem that a space volume required for suppressing the calorific value of the LED elements and the power supply control circuit decreases and the temperature of electric and electronic components such as a choke coil or semiconductor elements constituting the power supply control circuit elevates up to an undesired level. Since lifespan of electric and electronic components is greatly affected by heat, in an LED light source required with long lifespan, it is necessary to efficiently cool the electric and electronic components in order to suppress such a temperature rise, and particularly for a large capacity LEI) light source, that necessity increases.
For the large capacity LED light source device as described above, Patent document 1 proposes a light source device wherein leakage of a coolant from a cooling system for cooling the light source device is detected, and damage to a light source or a power source due to adhesion of the coolant can be prevented, but it is not mentioned to efficiently cool the electric and electronic components in order to suppress a temperature rise of a power supply control circuit, it is still insufficient from the viewpoint of securing stable operation of the control circuit and making the lifespan longer.